when pressing Enter after typing in a text input field (some users in the wild do this, our pretesters did not come up with this idea), focus is not kept in the text field.

With a single line text filed, pressing Return results in a behaviour like one pressed the browsers back button. In Firefox and Chrome LS intercepts with a "Don't use your browsers navigation" message. In IE the previous survey page is retrieved.

With a multiple line text field, in Firefox, Chrome, IE the field is blanked.

I Think thi would not occure if while pressing Enter the focus would be kept in the field. Focus should only leave the field when pressing Tab or when cklicking outside.